Pinch rolls for billet pusher



March 22, 1955 C o, CARLSON ETAL 2,704,611

PINCH ROLLS FOR BILLET PUSHER Filed Oct. 1, 1952 3 Shee ts-Sheet l Mamh 1955 c. o. CARLSON ETAL 2,704,611

PINCH ROLLS FOR BILLET PUSHER Filed Oct. 1, 1952 3 Sheets-Sheet 2 B 4% AWLM/ Adidas March 22, 1955 c, o, CARLSQN AL 2,704,611

PINCH ROLLS FOR BILLET PUSHER Filed Oct. 1, 1952 5 Sheets-Sheet 3 CZAYPZWQ' Q (4EL50/V and HE'EEZFET C 51667 140762 AMMA. Aw

United States Patent Ofiice 2,704,611 Patented Mar. 22, 1955 PlNCH ROLLS FOR BILLET PUSHER Clarence 0. Carlson, Chagrin Falls, and Herbert C. Felgemacher, Cleveland, Ohio, assignors to United States Steel Corporation, a corporation of New Jersey Application October 1, 1952, Serial No. 312,488

3 Claims. (Cl. 214-23) This invention relates to improved pinch rolls for motivating a ram used to push billets from a reheating furnace.

In the steel making art a reheating furnace is used for heating semifinished shapes to temperatures suitable for further rolling. The present invention is concerned with a type of reheating furnace which has a reciprocable ram situated behind its back wall adapted to enter the heating chamber and push heated billets longitudinally out the front into a rolling mill. The ram is motivated by pinch rolls which engage its upper and lower faces, and it is supported in a trough which can be shifted laterally to enable it to be guided accurately into engagement with the billets. Since the ram is continually exposed to the furnace temperature, frequent replacement is necessary. In previous installations with which we are familiar, it has been necessary to remove the top pinch roll before the ram can be removed and replaced. Consequently replacement is cumbersome and time consuming.

An object of the present invention is to provide improved pinch rolls which enable the ram to be removed and replaced without dismantling the rolls.

A more specific object is to provide improved pinch rolls which have mating circumferential recesses through which the ram can be withdrawn without necessitating removal of the top pinch roll.

In accomplishing these and other objects of the invention, we have provided improved details of structure, a preferred form of which is shown in the accompanying drawings, in which:

Figure l is a top plan view of a portion of a heating furnace, a ram, and pinch rolls for motivating the ram constructed in accordance with the present invention;

Figure la is a continuation of Figure 1 showing the back portion of the ram and its support means;

Figure 2 is a side elevational view of the structure shown in Figure 1;

Figure 2a is a continuation of Figure 2 showing in side elevation the back portion of the ram and its support means;

Figure 3 is a longitudinal vertical sectional view on a larger scale through the pinch roll stand;

Figure 4 is a sectional view on a still larger scale taken on line IV-IV of Figure 3; and

Figure 5 is a sectional view similar to Figure 3, but showing the manner of withdrawing the ram through the pinch rolls.

Figures 1 and 2 show a portion of a billet reheating furnace which includes a back wall 10, a door 12 therein and a hearth 13. Billets B are supported on said hearth for heating to an appropriate working temperature. An elongated ram 14 is supported behind the door 12, through which it is adapted to enter the furnace and push heated billets one by one out the other side. The forward end of the ram has at least one projector 15 to hold it in engagement with the end of a billet.

As shown in Figures 1a and 2a, the support means for the ram 14 includes two longitudinally spaced apart pairs of pedestals 16 and 17 which carry transverse guideways 18 and 19. A longitudinal guide trough 20 is mounted for transverse adjustment on these guideways, and receives the back portion of the ram. The ram is motivated by top and bottom pinch rolls 21 and 22 situated between the end of the trough 20 and the furnace door 12 (Figures 1 and 2). The top pinch roll is driven by a reversible motor 23 and speed reducer 24. The motor 23 and door 12 are controlled from a common station 25 (Figures 1a and 2a). Adjacent this station the guide trough 20 carries a handle 26 by which the operator can adjust the lateral position of the ram. During such ad ustment the points at which the pinch rolls grip the ram act as a fulcrum. Preferably a water spray device 27 is located at the back of the furnace to cool the ram (Figures 1 and 2).

Figures 3 and 4 show in greater detail the mounting means for the pinch rolls 21 and 22. These rolls are rotatably mounted in antifriction bearings 28 in upper and lower chocks 29 and 30. The upper chocks 29 are fixedly mounted in a pair of transversely spaced housings 31 and 32, and the top roll carries a shaft coupling 33 which extends outside the housing 32 and is connected with the speed reducer 24. The lower chocks 30 likewise are carried in the housings 31 and 32, but are movable vertically therein. A yoke 34 is pivoted to the housings on a transverse shaft 35. A pair of fluid pressure cylinders 36 are pivotally connected to the base of the roll housings and have piston rods 37 pivotally connected to the free edge of the yoke. The midportion of the yoke extends under the lower bearing chocks 30. The cylinders have fluid connections operated from the control station 25. During normal operation of the ram the cylinders urge the bottom pinch roll 22 upwardly toward the top pinch roll 21, and the ram thus is gripped between these rolls.

The mechanism thus far described, apart from the novel pinch rolls, is known and therefore is not described in greater detail. It is seen that the projector 15 on the end of the ram prevents removal of the ram simply by backing the pinch rolls. In the absence of the novel features of the present invention, it has been necessary to remove the top pinch roll 21 to remove and replace the ram.

In accordance with the present invention, the top and bottom pinch rolls 21 and 22 have mating circumferential recesses 38 and 39 respectively. Preferably these recesses are located adjacent one of the roll housings. When the operator wishes to remove the ram 14, he pulls the handle 26 to remove the back end of the ram sideways away from the recessed ends of the rolls. The ram thus pivots about a vertical axis defined by the points at which the rolls grip it, and it assumes an oblique position with respect to the roll axes. Next the rolls are driven in a direction to back the ram away from the furnace. The projector 15 on the ram thus is brought into line with the mating recesses 38 and 39, through which it can be readily withdrawn. If additional clearance is needed, the pressure in cylinders 36 can be released to lower the bottom pinch roll 22. The ram is installed merely by reversing the foregoing steps, with the pressure in the cylinders released.

From the foregoing description it is seen that the present invention affords a very easily operated and simple means for removing a ram from pinch rolls. Use of the invention eliminates the former need for removing the top pinch roll before removing the ram.

While we have shown and described only a single emb od1ment of the invention, it is apparent that modifications may arise. Therefore we do not wish to be limited to the disclosure set forth but only by the scope of the appended claims.

We claim:

1. An apparatus for pushing billets from a heating furnace comprlsmg a pair of roll housings, top and bottom pinch rolls rotatably mounted in said housings, reversible drive means connected to one of said rolls, both of said rolls having working surfaces occupying the major portron of their lengths, a slender elongated ram gripped between said working surfaces and having a relatively short width in contact therewith compared with the length of these surfaces, rotation of said rolls being adapted to propel said ram, a billet engaging projection on one end of said ram having a dimension which prevents its passage between said working surfaces, and means for pivoting said ram about its point of engagement with said working surfaces as a fulcrum to align said projection with a billet, at least one of said rolls having an annular recess occupying a minor portion of its length beyond one end of its working surface adjacent one of said housing, pivotal movement of said ram also being capable of aligning said projection with said recess to permit passage of said projection through said recess and removal of the ram from the rolls.

2 An apparatus for pushing billets from a heating fur nace comjfrising a pair of roll housings, top and bottom pinch ro s rotatably mounted in said housings for rotation on horizontal axes, means urging said bottom roll toward said top roll, reversible drive means connected to said top roll, both of said rolls having working surfaces occupying the major portion of their lengths, a slender horizontally extendingelongated ram gripped between said working surfacesand having a relatively short width in contact therewith compared with the length of these 10 surfaces, rotation of said rolls being adapted to propel said ram, a billet engaging projection on one end of said ram having a vertical dimension which prevents its passage between said working surfaces, and means for pivoting said ram on a vertical axis about its point of engage- 1 ment with said working surfaces as a fulcrum to align said projection with a billet, at least one of said rolls having an annular recess occupying a minor portion ofits arms length beyond one end of its working surface adjacent one of sa d housings, pivotal movement of said ram being capable of aligning said projection with said recess to permit passage of said projection through said recess and removal of the ram from the rolls.

3. An apparatus as defined in claim 2 wherein both of salrld rolls have annular recesses which mate with each at eri References Cited in the file of this patent UNITED STATES PATENTS France Aug. 23, 1921 

